Tests: cap CI extension batch concurrency

scripts/test-planner/planner.mjs

@@ -1359,6 +1359,24 @@ export const formatExecutionUnitSummary = (unit) =>
     unit.maxWorkers ?? "default",
   )} surface=${unit.surface} isolate=${unit.isolate ? "yes" : "no"} pool=${unit.pool}`;
 
+function resolveSurfaceAwareTopLevelParallelLimit(context, units, defaultLimit) {
+  if (!context.runtime.isCI || context.noIsolateArgs.length === 0) {
+    return defaultLimit;
+  }
+
+  const sharedExtensionUnits = units.filter(
+    (unit) => unit.surface === "extensions" && !unit.isolate,
+  );
+  if (sharedExtensionUnits.length <= 1) {
+    return defaultLimit;
+  }
+
+  // Shared extension batches can each retain multiple GiB in CI. Limit that
+  // phase to two concurrent lanes so provider-contract checks are not starved
+  // behind unrelated memory-heavy extension suites.
+  return Math.min(defaultLimit, 2);
+}
+
 export function explainExecutionTarget(request, options = {}) {
   const context = createPlannerContext(request, options);
   context.noIsolateArgs =
@@ -1492,7 +1510,11 @@ export function buildExecutionPlan(request, options = {}) {
     context.noIsolateArgs.length > 0
       ? context.executionBudget.topLevelParallelLimitNoIsolate
       : context.executionBudget.topLevelParallelLimitIsolated;
-  const defaultTopLevelParallelLimit = baseTopLevelParallelLimit;
+  const defaultTopLevelParallelLimit = resolveSurfaceAwareTopLevelParallelLimit(
+    context,
+    selectedUnits,
+    baseTopLevelParallelLimit,
+  );
   const topLevelParallelLimit = Math.max(
     1,
     parseEnvNumber(env, "OPENCLAW_TEST_TOP_LEVEL_CONCURRENCY", defaultTopLevelParallelLimit),

test/scripts/test-planner.test.ts

@@ -83,6 +83,40 @@ describe("test planner", () => {
     artifacts.cleanupTempArtifacts();
   });
 
+  it("caps CI extension batch concurrency when multiple shared batches are scheduled", () => {
+    const env = {
+      CI: "true",
+      GITHUB_ACTIONS: "true",
+      RUNNER_OS: "Linux",
+      OPENCLAW_TEST_HOST_CPU_COUNT: "4",
+      OPENCLAW_TEST_HOST_MEMORY_GIB: "16",
+    };
+    const artifacts = createExecutionArtifacts(env);
+    const plan = buildExecutionPlan(
+      {
+        profile: null,
+        mode: "ci",
+        surfaces: ["extensions"],
+        passthroughArgs: [],
+      },
+      {
+        env,
+        platform: "linux",
+        writeTempJsonArtifact: artifacts.writeTempJsonArtifact,
+      },
+    );
+
+    const sharedExtensionBatches = plan.selectedUnits.filter(
+      (unit) => unit.surface === "extensions" && !unit.isolate,
+    );
+
+    expect(plan.runtimeCapabilities.runtimeProfileName).toBe("ci-linux");
+    expect(plan.executionBudget.topLevelParallelLimitNoIsolate).toBe(4);
+    expect(sharedExtensionBatches.length).toBeGreaterThan(1);
+    expect(plan.topLevelParallelLimit).toBe(2);
+    artifacts.cleanupTempArtifacts();
+  });
+
   it("scales down mid-tier local concurrency under saturated load", () => {
     const artifacts = createExecutionArtifacts({
       RUNNER_OS: "Linux",